Chapter XIX: Lead and Its Compounds (5)

It will be thus observed that there has been a progressive diminution in the number of cases of lead poisoning in the pottery trade, a diminution that is still proceeding, judging from the returns of the first half of the year 1901. The cases reported for the six months, January-June, in the last four years are:--

1898 1899 1900 1901
200 165 110 59

“In the course of three years the amount of lead poisoning has been reduced to one-fourth of that reported in 1898.” The manufacturers attribute this result to the monthly medical examination of women and young persons brought into contact with lead.

An accidental delay in the passage of these pages through the press allows me to add a further note upon the attitude of the Home Office and the pottery manufacturers in regard to the use of fritted lead compounds, the suggested standard solubility, and the use of leadless glazes, and thus to bring up to date the history of this important trade inquiry, probably the last of the large industrial conflicts that will be submitted to arbitration. The questions at issue between the Home Office and the manufacturers were referred to arbitration, Lord James of Hereford being chosen as umpire. The Court sat at Stoke-on-Trent on 7th November 1901, and subsequent days. Mr Chester Jones acted as arbitrator for the Home Office, and Mr Llewellyn for the manufacturers; the counsel being, Mr Cripps, K.C., and Mr H. Sutton, for the Home Office; Mr Fletcher Moulton, K.C., for the manufacturers; and Mr Colefax for the operatives. Evidence was given by Professor Thorpe, Mr Wilton Rix; Dr Wilkin, director of large potteries, Dresden; Mr Alström, of the Rorstrand Potteries, Stockholm; Dr T. M. Legge; Miss A. M. Anderson, Principal Lady Inspector of Factories; and myself, on behalf of the Home Office. The principal points urged were: the possibility of using leadless glazes for certain kinds of ware; the greater safety of fritted lead compounds over raw lead; the greater freedom of Continental potteries from plumbism, where most, if not all, of the lead was fritted, than is the case in Staffordshire; and, in a general way, the better structural arrangements in Continental potteries than in those at home. On behalf of the manufacturers, Messrs W. H. Grindley, G. E. Meakin, H. J. Johnson, J. L. Whittaker, and J. Sherwin gave evidence. It was admitted by the witnesses on both sides that there had been since the introduction of the Special Rules 1898 a very notable decline in the number of cases of plumbism in Staffordshire, and that towards this happy circumstance better ventilation, greater personal cleanliness on the part of the workpeople, and systematic medical examination had doubtless contributed. The main part of the inquiry centred round the subject of fritting the lead for the glaze. It was demonstrated by Professor Thorpe that excellent results could be obtained by the use of vitrified lead, which was soluble to the extent of only 2 per cent. in .25 per cent. of hydrochloric acid. The manufacturers having previously intimated to the Home Office their willingness to accept a 5 per cent. standard solubility as the test of lead in their glazes, wished to recede from this position, and at the time the Court was sitting, claimed the right not to be bound by this or any other test of solubility. In fact, it was admitted that many of the manufacturers had returned to the use of 30 to 40 per cent. of raw lead in their glazes. As to the greater safety in the use of fritted lead compounds of the low solubility insisted upon by Professor Thorpe there can be no question. There never will be absolute safety so long as lead in any form is used; a 2 per cent. soluble fritted lead compound must be much less harmful if swallowed than one containing lead which has a solubility of 5 per cent. or more.[71] My contention, like that of Professor Thorpe, was that the .25 per cent. of hydrochloric test was not at all a hard one; that while this was the amount of hydrochloric acid present in the gastric juice, the test proposed was not so severe as that which would be carried on in the human stomach, where there was a higher temperature, greater agitation, and therefore better admixture of the contents.

It is unnecessary here to reproduce the evidence in detail either for or against the recommendations of the Home Office, which were based upon the Thorpe-Oliver Report; but I may mention one or two additional facts. While the Court was sitting, a male dipper of 20 years’ experience, and who had never been ill, requested permission of Lord James to give evidence. This was gladly complied with. The evidence tendered was directed against the proposed monthly examination of males employed in lead processes. The operative simply wished to assert his right to work in lead even if he was the subject of plumbism, to express his unwillingness to submit to periodical medical examination, and to state that he objected to be bound by the arbitrary order of the certifying surgeon either for temporary or permanent suspension. In a word, he stated that he and his comrades knew the risks of their calling, and they were prepared to take them. He appealed against the application of all official restraint, which he regarded as of too coercive a character. When working men, in whose interests well-meant efforts are being made to render their occupation more healthy, prefer to court death and to throw their wives and families upon the ratepayers rather than forego the loss of a few weeks’ wages so that they may regain their health, the difficulty of bringing into line the many conflicting forces is at once apparent.

To the fritting of lead compounds the manufacturers raised many objections. It was stated that, quite apart from the expense, their use was impracticable. Mr W. H. Grindley of Tunstall stated that he had tried fritted lead, but had relinquished it, as its use had involved him in a financial loss of some hundreds of pounds in a few weeks. Mr Henry J. Johnson and other manufacturers gave similar evidence.

Quite unexpectedly, on the fifth day of the sitting of the Court, Lord James announced his intention of not carrying the inquiry further. Balancing the various conflicting issues at stake, and influenced by the reduction in the number of cases of lead poisoning from 12 to 3.5 per cent. in the four years’ operation of the Special Rules, he postponed the arbitration for eighteen months, during which, putting the manufacturers on their honour, he looked to them to rigidly give effect to the Special Rules of 1898; to take a lesson from Continental manufacturers; to try fresh experiments with fritted lead, and to reduce them to the lowest possible solubility consistent with a satisfactory production of their ware; also to come to some understanding with the workpeople in regard to founding a mutual assurance fund. As the whole subject is to be again discussed in eighteen months, it would ill become me to do more than simply state these facts, and to express the hope that by a loyal adherence to the special regulations the amount of lead poisoning in Staffordshire may meanwhile still further decrease.

_Chromo-lithographic Works and Transfer Making._

In the printing of coloured trade advertisements and wrappers there is frequently used metallochrome powder, known under various names, _e.g._ “flake white,” “china white,” etc. Usually the dry powder is dusted on the sheets of paper by hand and dusted off again by young women or lads, an operation that is extremely dusty, and too often carried on in workrooms totally unprovided with any artificial means of ventilation. Practically speaking, the manufacture of transfers for giving coloured impressions to pottery is a similar operation. The coloured impressions are made upon paper which, when applied to china and earthenware about to be fired, allow of the floral design and pictures being transferred to plates, cups, and saucers, etc. Under all circumstances, whether it is the making of transfers for pottery work, covers for fancy tins of biscuits, mustard, tobacco, etc., or coats-of-arms for railway carriages, the occupation is not only dusty but is dangerous, owing to the fact that metallochrome powder often contains as much as from 50 to 60 per cent. of white lead. In the manufacture of transfers the workers, usually girls, throw the powder loosely on the paper and tilt it from side to side, or what is more common, they gently rub the powder all over the paper by means of a soft cloth or a pad of chamois leather, the superfluous powder being removed by shaking. In visiting factories where transfers are made both at home and on the Continent, I have been struck by the extreme pallor of the workers; frequently they have complained of splitting headache and severe abdominal pains. Nearly all the workers presented a deep blue line on their gums. In Limoges, where large quantities of coloured porcelain are made, the introduction of transfers into the industry took place only about twenty years ago, and it was not until several fatal cases of lead poisoning had occurred that the plumbism was traced to its cause, viz., the making of transfers. Many of the girls had succumbed to that extremely severe and often suddenly developed form of Saturnine affection of the brain, which is attended by epileptiform convulsions, and known as lead encephalopathy. It is when metallochrome powder is used in the dry form, and therefore dusty, that there is danger. When mixed and moistened as in coloured printers’ ink, and the printing is done by machinery, there is no danger. Men, however, have suffered from plumbism after mixing “flake white” and varnish. This is not a dusty process, but there is considerable danger when spirituous materials are used along with lead.

Much of the risk to health in this trade can be overcome by diminishing the amount of white lead in the metallochrome powder. Experience shows that this is often present in excess of what is necessary. A less harmful metal, too, might in several instances be substituted for lead. Barium has been suggested, but time and trial alone can tell whether even the use of barium is quite free from danger. Animals can be fed upon barium salts, and apparently thrive when they would die if given the same quantity of lead carbonate. It is a heavier metal than lead, and on the whole may be said to be safer. Magnesia has also been recommended as a substitute for white lead in the metallochrome powders. The trade of transfer making is one in which, fortunately in one sense for the workers, employment is irregular. Under any circumstance it is an occupation in which the workers should have some alternation of employment, and in which no young person should be engaged, no food should be eaten in the workroom, overalls ought to be worn, and before leaving the factory the hands and face of each worker, should be washed. Not only should adequate lavatory accommodation be provided, but sufficient time should be given by the masters before break, for the workers to wash. In this, as in all trades in which lead is used, the individuals should be subjected to periodical medical examination--experience in the potteries, for example, having shown how very beneficial this has been in preventing plumbism. Such an examination often succeeds in eliminating persons who are susceptible to lead before they have worked too long at the trade. In Limoges, so impressed were several of the large porcelain makers by the great susceptibility of young women to plumbism, that they now only employ men in the manufacture of transfers. The work, too, is no longer conducted on open tables, but in closed glass cases, through openings which are guarded by indiarubber, the hands of the workman are thrust, so that the operation of “laying on” is conducted under cover, the dust created being drawn away by strong aspiration on the distal side of the enclosed space. Since the introduction of this method of making transfers, plumbism has disappeared from most of the large porcelain works in Limoges. In Staffordshire a similar method of transfer making has also been adopted, and with equally satisfactory results to the workpeople.

Eleven cases of lead poisoning were notified to the Home Office as having occurred in litho-transfer works during 1899.

_Tile-making and Manufacture of Porcelain Stoves._

The manufacture of tiles for useful and decorative purposes, such as the floor of entrance halls, hearths, sides of fireplaces, and stoves, is a large and increasing industry. The pressing of clay into the form of tiles is done by machinery, and although it is a dusty process, there is usually in operation at the time the pressing is done a strong aspirating draught brought into play, whereby the dust is removed from the face of the worker. The tiles when dried are subsequently dipped in glazes often rich in lead. Usually the lead which enters into the composition of the glaze for majolica tiles is fritted; but some manufacturers have until recently been in the habit of using only raw lead, and it was occasionally in their factories that lead poisoning occurred. The opportunities for a worker becoming leaded are during the dipping, cleaning, or painting. In some of the factories visited by Professor Thorpe and myself, we saw mechanical dippers in use which gave promise of superseding hand-dipping and of abolishing the necessity for cleaning and trimming the edges of the tile. Employment of mechanical dippers and of fritted lead compounds, conforming to the solubility standard required by the Home Office, with enforcement of the Special Rules, would pretty well abolish plumbism in this industry.

During the manufacture, at Velten in Brandenburg, of glazed tiles for making earthenware stoves, there recently occurred a considerable amount of lead poisoning among the operatives,[72] due to the glazing of tiles with oxide of lead. The outbreak is of sufficient importance to be mentioned here. The glazing material is made, first, by firing together lead oxide and tin in the proportion of three to one. To the compound thus obtained there are added felspar, marine salt, and quartz. These are mixed together, and subsequently exposed to a great heat so as to form a fritt. The vitrified material thus obtained is crushed, finely pulverised and mixed with water, while the thick liquid is applied to the surface of the tiles, which are afterwards heated in a special furnace. During these operations there are many opportunities for the workmen to become poisoned by lead. In the act of crushing, a considerable amount of dust rich in lead salts rises into the atmosphere. Rasch caused some of the air to pass through cotton-wool, and he thus arrested the dust. The lead in this he estimated as sulphide. The quantity found by him in 100 litres of air varied between 0.0012 to 0.0066 gramme, which was equivalent to an amount of lead oxide entering into the lungs during the twelve hours’ work in the factory of 0.05 to 0.6 gramme. Upon the clothes of the workmen he obtained as much as 3 to 4.8 grammes. It was found that all the lead in the fritt had not been converted into an insoluble form. There was at least one-hundredth part in the form of lead oxide, a circumstance which rendered the glaze harmful to those who dipped the tiles, and also to those who handled them after dipping. It is needless to say that where this industry is carried on, precautions should be taken similar to those in use in the potteries, care being taken to have the fritting of the lead carried on in well-ventilated places, and the grinding of the fritt done in enclosed machinery.

_Washing of Lead-workers’ and Painters’ Clothes._

In my Gulstonian Lectures on Lead Poisoning, I make mention of the fact that dogs which had slept on the coats or jackets of their masters, who were lead smelters in the vales of Durham, sometimes suffered from colic; also that a peculiar epidemic of Saturnine poisoning occurred in France in women who had simply washed the clothes of their husbands, who were workers in lead factories. One of the main reasons for the White Lead Commission recommending the wearing of overalls when at work was that the Committee ascertained that the clothes of several of the female workers, which were often dust-laden, became the bedclothes of the family at night. Lead dust is always a danger, so, too, may be the bespattered working clothes of house painters. A woman, thirty-six years of age, consulted me at the Newcastle Dispensary on account of anæmia, headache, and double wrist drop. In addition she had a well-marked blue line on her gums. There was no difficulty in diagnosing the case as one of plumbism, the difficulty was rather in tracing the lead poisoning to its source. She was a widow and had never worked in any factory, nor, so far as she knew, had she ever been brought into contact with lead. She simply attended to her domestic duties. On inquiry I found that since her husband’s death, in order to increase her income, she had taken to reside with her two male lodgers--her own brother and a nephew. Both were house painters, and they wore the ordinary white jackets and trousers of the artisan. The patient was in the habit of washing their clothes once a week, which were frequently very much discoloured, especially those of the younger man, the nephew. I asked for a bottleful of the water removed from the washtub when she washed the clothes. This water was dirty brown in colour, and contained a good deal of sediment. I submitted it to Dr Bedson, Professor of Chemistry at the College of Science in Newcastle, who reported the presence of a very large quantity of lead in suspension in the water, and a small quantity in solution. That the woman’s ill-health and paralysis of the hands were due to Saturnine poisoning there was not the least doubt, for under medicinal and electrical treatment and cessation on her part of the weekly washing of the painters’ clothes, health was gradually regained and muscular power restored. It is known that women who wash the overalls, etc., in white lead factories occasionally suffer from plumbism.

_Lead Foil Manufacture._

Makers of lead foil which is to be subsequently used for the tops of bottles or for wrapping round tobacco, snuff, and cheese, occasionally suffer from plumbism; so, too, do those who handle and fix the lead discs over the corks of bottles. On analysis the metallic foil which envelops Roquefort cheese has been found to contain 12 parts of tin and 85 of lead, among other substances, while in that which envelops Angelots cheese there has been found as much as 95 per cent. of lead. Tobacco smokers and chewers have suffered from using tobacco kept in metallic dishes, and I have had professional experience of the very bad effects of the use of snuff wrapped in leaden foil. An attempt is being made to substitute parchment for lead discs for bottles.

_Shoe-finishing and Staining by Lead Compounds._

A few months ago, owing to several shoe finishers in Northampton having been thrown upon their benefit societies, all suffering from the same type of symptoms, ultimately certified to be lead poisoning, the circumstance was necessarily brought under the cognisance of the Factory Inspector for the district. The men worked in the same factory. On investigation it was found that they were in the habit of using, for finishing the bottoms of shoes, certain powders, known in the trade as Chinese red and yellow chrome. These contained lead compounds. In the manipulation of the powders to stain the boots and shoes with, a considerable amount of dust arises. The process is thus described by Mr Wright, H.M. Inspector. Dry China-red powder is by means of a sponge dusted on to the sole of a boot, a piece of fine glass-paper is then used to scour the colour into the leather, a small quantity of grease is subsequently applied, and the sole is polished with a dry cloth. The workman, during the whole of the process, has to bend down closely over the boot, and thereby inhales the coloured dust. Sometimes chrome-yellow is mixed with the China-red. It was found necessary by the Home Office to interdict the use of these powders, less harmful substitutes being suggested.

_Lucifer Matches containing Lead._

In order to make matches strike softly, and in other instances with the view of making matches free from yellow phosphorus, various compounds of lead have been introduced into the paste for heading the lucifers. The mixing of the ingredients and the manipulation of the paste were attended by such an amount of sickness among the workers that their use has been discarded, for it was found that although less painful, lead poisoning was just as serious a malady as that caused by phosphorus.

_Buffing of Brass Cocks and Plumbism._

In buffing brass cocks upon rapidly revolving wheels covered with leather, the surface of which is kept coated with emery powder, several of the men have become ill, and shown signs of lead poisoning. Buffing is done so as to smooth the brass cocks after casting. In what is known as “gun” and “pot” metal, lead is sometimes present to the extent of 5 to 6 per cent.